Originally Posted by
hxhbk
The requirement for digital registration on entry does not apply to countries (such as the USA currently) that are not on the current list of high risk area or area of variant concern. The list is updated periodically so checking the list for the latest change is certainly recommended.
True, though the OP asked about travel from London, which is high risk. I think the form even tells you whether you have to complete it or not when you select the countries you've been in, which is a useful check.
For info, the RKI list of which countries are high risk/virus variant areas is updated every Friday (usually around lunchtime) and any changes take effect from the following Sunday:
https://www.rki.de/DE/Content/InfAZ/...biete_neu.html